San Diego Zoo giant panda cub playful during latest test

The San Diego Zoo's giant panda cub was in a very playful mood during his latest examination.

It took three sets of hands to measure and examine the new cub, Xiao Liwu, on Wednesday. They examined his eyes, teeth, heart and lungs.

The cub, strong and very playful, had no interest in sitting still. Vets say Xiao Liwu is already 24.6 inches long and weighs 19.4 pounds. Zoo officials say Xiao Liwu has gained a lot of muscle in his back legs from climbing trees and other activities. More of his teeth are also growing in.

Experts say panda cubs may appear clumsy, but they learn how to safely tumble and fall very quickly. The pandas are on a research loan from China.